NSW Premier Gladys Berejiklian said this morning (Friday) she's "asking people to brace themselves", adding she was "absolutely concerned" about the COVID-19 outbreak that's developed in Sydney's Northern Beaches area that, as of yesterday, has grown to 17 cases. 

"We are going to have a considerable amount of cases come during the day and that's because people have come forward for testing," Gladys told the Seven Network.

She'll be giving a presser at 11am, but until then here's everything you need to know about the outbreak.

1. Where did the outbreak develop?

According to Gladys, genomic testing has revealed the coronavirus strain originated overseas but it isn't known exactly where the outbreak started.

2. Where are the hotspots?

Avalon: Hungry Ghost Café, 3/48 Old Barrenjoey Road: Monday 14 December 9.30am to 11am

Avalon Beach: Avalon Bowlo (bowling club), 4 Bowling Green Lane: Sunday 13 December, 5pm to 7pm & Tuesday 15 December 3pm to 5pm

Avalon Beach: Bangkok Sidewalk Restaurant, 1/21-23 Old Barrenjoey Road: Monday 14 December 7pm to 8pm

Avalon Beach: Barramee Thai Massage and Spa, 4/42-44 Old Barrenjoey Road: Monday 14 December 2pm to 3.30pm

Avalon Beach: Sneaky Grind Café: Monday 14 December 10.30am to 11am

Narrabeen: The Narrabeen Sands Hotel: Tuesday 15 December 6pm to 7.30pm.

Palm Beach: Palm Beach women's change rooms: Sunday 13 December 9am to 9:15am

Palm Beach: Coast Palm Beach Café, Barrenjoey Road: Sunday 13 December 10am to 11am

3. What if I've been to one of these hotspots? 

If you live in one of these hotspots, you must immediately self-isolate and get a coronavirus test. You'll need to remain in quarantine for the full two weeks, even if your initial test is negative.

Anyone who lives from The Spit Bridge in Manly to Palm Beach – about 250,000 people – has been asked to stay at home for the next few days.

4. What's the latest on border restrictions?

Since the outbreak was announced, states and territories are now scrambling to impose border restrictions, which isn't looking too good for people's Christmas travel plans.

For VIC and QLD, anyone who was in the Northern Beaches on or since December 11 must get tested and self-isolate in their home or accommodation for 14 days.

Anyone arriving in QLD after 1am on Saturday will need to do a mandatory, self-funded quarantine.

Anyone arriving into WA from NSW will now need to self-isolate for two weeks.

Tassie is shut to anyone who's been in the Northern Beaches on or since December 11.

Those arriving into NT who were in the Northern Beaches on or since December 11 will also need to undertake mandatory, supervised quarantine in Alice Springs or Darwin.

We'll update this story as the situation develops, but for live updates, check out The Guardian's rolling coverage here.

UPDATE: 18th December 2020, 11:40pm: At an 11am a press conference this morning, the premier confirmed that the state had recorded 10 additional cases of coronavirus. The total number of cases in NSW now sits at 28. Catch our full update here.

If your head is a little scrambled, make sure you pop over to WHO.int to get all of your official COVID-19 updates.

Written by Sangeeta Kocharekar, an American-born, Sydney-based writer at MTV. Photos from her pre-COVID-19 days as a travel writer are here.